From: Mark Thom <markjordanthom@gmail.com>
Date: Thu, 18 Nov 2021 16:35:00 +0000 (-0700)
Subject: unmark cell bits in occurs check
X-Git-Tag: v0.9.0^2~129
X-Git-Url: https://git.sagredo.dev/?a=commitdiff_plain;h=a0a86d0f6266503f6de14bcfde2e6a894301f7ac;p=scryer-prolog.git

unmark cell bits in occurs check
---

diff --git a/src/machine/machine_state_impl.rs b/src/machine/machine_state_impl.rs
index 1caa8a96..47019772 100644
--- a/src/machine/machine_state_impl.rs
+++ b/src/machine/machine_state_impl.rs
@@ -882,6 +882,8 @@ impl MachineState {
 
         if !value.is_constant() {
             for addr in stackful_preorder_iter(&mut self.heap, value) {
+                let addr = unmark_cell_bits!(addr);
+
                 if let Some(inner_r) = addr.as_var() {
                     if r == inner_r {
                         occurs_triggered = true;